Skid steer vehicles such as skid steer loaders are a mainstay of construction work. In their most common configuration, they have two drive wheels on each side of a chassis that are driven in rotation by one or more hydraulic motors coupled to the wheels on one side and another one or more hydraulic motors coupled to the wheels on the other side.
The wheels on one side of the vehicle can be driven independently of the wheels on the other side of the vehicle This permits the wheels on opposing sides of the vehicle to be rotated at different speeds and in opposite directions. By rotating in opposite directions, the skid steer can rotate in place about a vertical axis that extends through the vehicle itself.
The vehicles have an overall size of about 10 by 12 feet, which, when combined with their ability to rotate in place, gives them considerable mobility at a worksite. It is this mobility that makes them a favorite.
Skid steer vehicles commonly have at least one loader (or lift) arm that is pivotally coupled to the chassis of the vehicle to raise and lower at the operator's command. This arm typically has a bucket, blade or other implement attached to the end of the arm that is lifted and lowered thereby. Most commonly, a bucket is attached, and the skid steer vehicle is used to carry supplies or particulate matter such as gravel, sand, or dirt around the worksite.
As a counterbalance to the loads provided at the front of the vehicle, skid steer vehicles typically have an engine that is located behind the operator. The radiator is also commonly disposed behind the operator, usually at the center rear of the vehicle.
A door or other access hatch is located at the very back of the vehicle to give the operator access to the engine and radiator from the very rear of the vehicle. Other doors and hatches may be disposed down the side of the vehicle or engine compartment instead of the rear to provide additional access.
One difficulty with rear engine access doors is their susceptibility to impact. Skid steer vehicles typically have a restricted view to the rear, preventing the operator from seeing behind the vehicle. Skid steer vehicles also spend a substantial amount of time traveling in reverse is close quarters. Skid steer vehicles are often operated in a rapid back-and-forth movement, making what are called “Y turns” as they move material from one pile to another perhaps several hundred times a day.
As a result, operators often misjudge the distance between the rear of the vehicles and obstacles and occasionally back skid steer vehicles into these obstacles, albeit at very slow speeds. Whenever a skid steer with a rear engine compartment door impacts an obstacle it is the door that suffers.
Even when the door is not damaged, however, the door hinges an the door latch may be damaged. The forces involved may not be great enough the actually damage the door itself, but it is often significant enough to tear or bend the hinges and latch, thereby either removing the door entirely, or jamming the door shut in its closed position
What is needed, therefore, is an improved skid steer vehicle having a door that is resistant to being damaged. What is also needed is a skid steer vehicle with a means for protecting the door hinges from upward rear impacts. What is also needed is a skid steer door that automatically protects the hinges without requiring additional operator input. What is also needed is a means for transmitting potentially damaging forces acting against the rear door directly to the frame or chassis. It is an object of this invention to provide these advantages. While not every claimed aspect of the invention provides all these advantages, each of these advantages is provided by at least one claimed aspect.